Circular knitting machine



. 21, 1956 H. s. BURDETT 2,759,342

, CIRCULAR KNITTING MACHINE Filed NOV. 10, 1954 3 Sheets-Sheet 1 EMU Aug. 21, 195 H. s. BURDETT CIRCULAR KNITTING MACHINE 3 Shets-Sheet 2 Filed Nov. 10, 1954 E ml mm Aug. 21, 1956 H. s. BURDETT CIRCULAR KNITTING MACHINE s Sheets-Sheet 3 Filed Nov. m. 1954 United States Patent Office G. Sfibbe & Co. company England, assignor to Limited, Leicester, England, a British Application November 10, 1954, Serial No. 468,073

Claims priority, application Great Britain November 10, 1953 7 Claims. (CI. 66-14) This invention appertains to circular knitting machines of the kind equipped with picker mechanisms for automatically effecting longitudinal displacement of needles whereby predetermined needles are systematically moved either to a knitting or to a non-knitting position, according to requirements.

The invention is primarily intended for application to circular knitting machines adapted to operate with oscillatory as well as with rotary motion and furnished with narrowing and widening pickers for the production of tubular knitted fabric with pouches.

In this regard the invention is principally applicable to single as well as to double cylinder seamless hosiery, i. e. hose or half hose, machines wherein narrowing and widening pickers are used for the production of heel and toe pouches, automatically, during oscillatory knitting.

A picker mechanism on a seamless hosiery machine can, of course, also be used for producing split-foot hosiery.

Moreover, for a reason shortly to be explained, the invention is more especially concerned with circular knitting machines of relatively small diameters, although there is no limitation in this respect.

Now in a conventional circular knitting machine of the kind concerned, the universally or otherwise suitably articulated pickers are arranged for action upon knitting butts provided on the needles, or on the needle-actuating sliders or jacks, as the case may be. To enable the picker mechanism in such a machine to effect a required selection or selections of the needles, it is necessary to provide knitting butts of different lengths and to arrange these butts in a predetermined set-out which it is not possible to vary. Thus, for instance, and as well known tothose acquainted with the knitting art, the needles in a circular seamless hose or half hose machine as heretofore constructed are arranged in two substantially semi-circular groups, viz. the instep and the heel and toe needles, and to facilitate movement of the instep needles to a non-knitting position and to enable the narrowing and winding pickers to perform their function during the knitting of a heel or toe pouch, the instep and the heel and toe needles, or the associated jacks or sliders, as the case may be, are provided with long butts for the instep needles or their associated jacks or sliders and short and medium butts for the heel and toe needlesthus particular set-out of the butts being incapable of variation. For this reason, the possibilities of selective manipulation of the needles and hence the knitting and patterning ranges of a machine of the kind herein referred to are limited. Quite apart from this, the fact that the pickers have heretofore been required to act on the knitting butts has made it necessary for the pickers and their holders or brackets to be located closely adjacent to the knitting cam system, or the appropriate knitting cam system, of the machine. This necessity has naturally restricted the space available around the machine both for bolt and similar cams and also for 2,759,342 Patented Aug. 21 1956 ancillary devices and attachments. The problems created by such restriction of space are, of course, more marked in machines of comparatively small diameters, and have heretofore been responsible for limiting the number of feeders (knitting stations) it was possible to provide. In this connection, for example, the existence of the narrowing and widening pickers in a circular seamless hose or half hose machine having a needle cylinder or cylinders of as small as say, 3 /2 in diameter, has heretofore made it difficult, if not impossible, to provide more than two feeders.

The object of the present invention is to provide, in a circular knitting machine of the kind herein referred to, an improved arrangement of the picker mechanism designed to obviate the foregoing difficulties and to provide certain advantages as will be hereinafter mentioned.

According to this invention the needles, or associated jacks or sliders, are provided with a set of butts separate and spaced axially from the knitting butts and some at least of which are adapted to be acted upon by pickers correspondingly spaced axially from and clear of the knitting cam system in conjunction with which they function.

Thus, the said butts spaced axially from the knitting butts are quite separate and distinct, thereby enabling the knitting butts to be of two or more varying lengths and to be arranged in contrasting groups or panels or interspersed in any pre-arranged set-out capable of being varied from time to time, according to knitting and patterning requirements.

It is mainly the intention that the separate butts spaced axially from the knitting butts shall also be of different lengths but in this case arranged in a pre-determined set-out for use in conjunction with a movable cam whereby the needles can, at required times, be so divided that some are moved to a non-knitting position whilst others are suitably disposed to take yarn and knit; in these circumstances the pickers are operable in conventional manner upon butts of the same length to vary the number of needles which knit in different courses. Accordingly, in applying the invention to a seamless hose or half hose machine, there is a substantially half round series of long, and a complementary series of shorter, separate butts, the shorter butts being arranged to be acted upon by narrowing and widening pickers spaced axially from and clear of the knitting cams. In this case the said long and shorter butts differentiate the instep needles from the heel and toe needles (in the same way as do the long and short knitting butts in a conventional seamless hosiery machine) and there is provided in the same or substantially the same plane as the narrowing pickers a withdrawable cam adapted, whenever it is rendered operative preparatory to the knitting of a heel or toe by oscillatory knitting, to act upon the long butts for the purpose of moving the instep group of needles to a non-knitting level.

By locating the pickers entirely clear of the knitting cam system, or the appropriate knitting cam system of the improved machine more of the annular space surrounding this system is made available for, say, additional knitting cams. In this connection an important advantage of the invention is that a circular seamless hose or half hose machine of relatively small diameter can be readily equipped with three instead of only the customary two feeders. Such a three-feeder machine accordingly constitutes a feature of this invention.

In order that the invention may be more clearly under stood and readily carried into practical effect, a specific example thereof embodied in a circular seamless hose or half hose machine of the superimposed rotary needle cylinder type will now be described with reference to the accompanying drawings, wherein:

Figure 1 is a vertical sectional view of so much of the head of the machine as is necessary to illustrate the application of the invention thereto,

Figure 2 is a developed layout of the top and bottom cam systems of the machine as seen from the insides of the cam boxes, and includes side views of representative top and bottom needle-actuating sliders,

Figures 3a and 3b are diagrams illustrating the respective layouts of the knitting butts and the lower, i. e. additional, butts on the bottom sliders, and,

Figure 4 is a plan view comprising the cams and the narrowing and widening pickers arranged for action upon the said additional slider butts.

Referring to Figure 1, it will be seen that the machine illustrated includes a bottom or plain rotary needle cylinder 1, surrounded by a stationary bottom cam box 2, a superimposed top or rib rotary needle cylinder 3 similarly surrounded by a stationary top cam box 4, double-ended latch needles such as 5 for operation in the said cylinders, and bottom and top sliders 6 and 7 respectively for actuating the needles and transferring the same from one cylinder to the other, according to knitting requirements. The top needle cylinder 3 is driven from the bottom cylinder 1 through the medium of gears 8 and 9 secured to the cylinders and two pinions 10 and 11 which are arranged to mesh with said gears and are in turn secured to a common vertical shaft 12.

The double axially opposed needle cylinders 1 and 3 in this example are of small diameter, e. g. in the order of 3 /2" or thereabouts, and the machine is equipped with three feeders, viz. a main feeder F and two auxiliary feeders F and P In the cam system located within and carried by the bottom cam box 2 there are provided, at the main feeder F the customary legging or forward stitch cam 13, the heeling or reverse stitch cam 14, a centre cam 15, various guard cams such as 16, 17 and 18 and a reverse welt cam 19 of the withdrawable bolt type (all shown in Figure 2). At the first auxiliary feeder F the bottom cam box 2 is furnished with a clearing cam 20, a stitch cam 21, an adjoining feed cam 22 of the withdrawable bolt type for determining whether or not raised needles shall knit at that feeder and a reverse welt cam 23 also of the withdrawable bolt type. Similarly, at the second auxiliary feeder F the box 2 is equipped with a clearing cam 24, a switch cam 25, a withdrawable feed cam 26 adapted, by virtue of being in or out, to determine whether or not cleared needles shall knit at the feeder F and a reverse welt cam 27 again of the withdrawable bolt type. Between the main feeder F and the second auxiliary feeder F in the bottom cam box 2 there is provided the customary main transfer cam 28 for use in the transference of needles from the bottom cylinder 1 to the top, cylinder 3.

The stitch cams at the three feeders F, F and F in the top cam box 4 are indicated at 29, 30 and 31 respectively. The numeral 32 indicates the main transfer cam in the top box for transferring needles from the top cylinder to the bottom cylinder. It is convenient here to mention that in the particular machine now being described, the various bolt earns 22, 23, 26 and 27 at the two auxiliary feeders in the bottom cam box 2, and also feed earns 33 and 35 and welt earns 34 and 36 of the bolt type at the same two feeders in the top cam box 4 are all controlled from an auxiliary control drum separate from the conventional main control drum of the machine.

The feed earns 33 and 35 are for use in determining whether or not needles in the top cylinder 3 shall knit at the auxiliary feeders F and F The direction of rotation of the needle cylinders is indicated by the arrow C in Figure 2, and by the arrow B in Figure 4.

Each needle-actuating slider 6 in the bottom needle cylinder 1 is furnished with three butts, viz. an upper or knitting butt 37, an intermediate or transfer butt 38 arranged to be acted upon by the bottom transfer cam 28, and a lower (additional) butt 39 (see Figures 1 and 2). The additional slider butts 39 are, therefore, located beneath the transfer butts 38 and thereby well spaced axially from the knitting butts 37. Of the circular series of additional slider butts 39 substantially half of them are long as indicated by the upper arcuate portion LB of Figure 38 whilst the remainder are shorter and of medium length as represented by the lower arcuate portion MB of the said figure. The two lengths of the additional butts 39 serve to differentiate the instep sliders from the heel and toe sliders. The illustrated set-out of the said additional butts cannnot be varied.

The knitting butts 37, on the other hand, may be of two or more different lengths arranged, as previously mentioned, in contrasting groups of panels or interspersed in any desired set-out which is capable of being varied from time to time, according to patterning requirements. Thus, the butts 37 may be long, medium or short, or any combination of these lengths, a typical set-out of the knitting butts is illustrated in Figure 3A wherein it will be seen that the two separated groups of such butts represented by the arcuate portions MB and MB are of medium length, whereas the butts of the intervening smaller groups indicated at SB and SE are short. Although, for convenience, the lay-outs of butts in Figures 3a and 3b have been separated it will, of course, be appreciated that, on the machine, these sets of butts 37 and 39 are disposed one above the other in suitably spaced horizontal planes. The central axis of the machine is indicated at a in both of the figures, and to show the correct relationship of the knitting butts 37 with respect to the additional slider butts 39, chain lines b, c, and d, e have been drawn on Figures 3a and 3b.

In the illustrated example, the bottom cam box 2 is combined with a lower subsidiary box or cam box extension 40 which, as will be appreciated from Figure l, is constituted by a modified form of the conventional casing ring serving to support this cam box. In the subsidiary box or extension 40 there is provided, immediately beneath the transfer cam 28 in the box 2, a movable /2=lift cam 41 of the bolt type (see Figures 2 and 4) adapted, when appropriately adjusted to act on the long additional bottom slider butts 39 of the semicircular series LB (Figure 3B) for the purpose of raising the corresponding needles 5 of the instep group to the non-knitting level customarily known as heeling height. Whenever such a division of the needles is effected preparatory to knitting a heel or a toe pouch, the shorter additional slider butts 39 of the group MB are permitted to remain at the low level L (see right hand side of Figure 2) with the corresponding, i. e. the heel and toe, needles positioned at the knitting level. In Figure 2, the knitting level and the heeling height are indicated at KL and HH respectively. To ensure that the bottom sliders 6 are held back in their tricks in the cylinder 1 there are provided, in the subsidiary box or cam box extension 40, straight cam-like components such as those indicated at 42, 43, 44, 45 and 46, for contact with the outer edges of the stems of the bottom sliders, these components being located in a horizontal plane spaced axially well beneath and clear of the bottom knitting cam system.

In this machine, the picker mechanism comprises two narrowing pickers 47 and 48 which are located below the straight components 42 and 44, immediately beneath the legging and heeling stitch cams at the main feeder F and a single widening picker 49 located at the back of the machine, i. e. nearly from the centre cam 15. The single widening picker 49 is, of course, at an appropriate higher level than the two narrowing pickers 47 and 48 at the front of the machine, but is nevertheless spaced axially well beneath the cam system in the bottom box 2. The pickers function during oscillatory knitting in the usual way, the narrowing pickers 47 and 48 serving to elevate appropriate shorter additional butts 39 of the semi-circular group MB and so raise needles of the heel and toe group to heeling height H and the Widening picker 49 acting to depress such butts and lower again previously raised heel and toe needles.

The /z=lift cam 41 is also used, when suitably set for action on slider butts 39, for the purpose of elevating bottom sliders 6 to bring their transfer butts 38 into the range of the main transfer cam 28 during transference of needles from the bottom to the top cylinder. A levelling cam 50 provided in the subsidiary box or cam box extension 40 is for action on additional slider butts 39 to depress the bottom sliders 6 to the level L after such a transference of needles.

Now for pressing-off needles in the bottom cylinder only whilst needles in the top cylinder retain their loops at the first auxiliary feeder F for the purpose of producing a separating course between one article and the next of a string, it is possible to put in the feed cam 22 and the reverse welt cam 23, these cams being used for this purpose in conjunction with a latch opening device with no yarn being introduced at the feeder F But since, as previously described, the cams 22 and 23 are controlled from an auxiliary control drum, it may in some circumstances be more convenient to operate the needles for pressing-off by means of cams controlled from the main control drum. Thus, for use in lieu of the cams 22 and 23 in the bottom cam box 2, there may, as shown in Figures 2 and 4, be provided in the subsidiary box or cam box extension 40 two withdrawable cams 51 and 52 adapted for action on the additional bottom slider butts 39.

By providing in the top cylinder 3 sliders 7 of the same form as the bottom sliders 6, that is to say top sliders with knitting butts 53, transfer butts 54 and additional butts 55 of different lengths, it is possible to use the said additional butts in conjunction with an additional transfer cam 56 (Figure 2) provided in an upper extension 57 of the top cam box 4, thereby increasing the needle transferring possibilities of the machine.

Referring now to Figure 4, which clearly illustrates the manner in which the narrowing and widening pickers and the cams 41, 50, 51 and 52 are distributed within the subsidiary box or cam box extension 40, it will be seen that a quality ring 58 common to all of the four stitch cams 13, 14-, 21 and 25 is provided for effecting simultaneous adjustment of the latter for quality. The ring 58 is set in an annular recess formed in the bed plate 59 of the machine (Figure 1) and is shiftable in the direction of the arrow D (Figure 4) to vary the quality. Each of the four stitch cams concerned is connected with a vertically disposed rod 60 the lower end of which is articulated to one arm 61a of a bell crank 61 fulcrummed at 62 within a bracket 63 which is secured, by screws 64, upon the bed plate 59. The other arm (not shown) of each bell crank 61 extends downwardly and is adapted to be acted upon by a block 65 attached to the quality ring 58. To enable it to be shifted for the purpose in view, the said ring is furnished with a lug 66 which is connected by a link 67 to a quality control member 68. This member is pivoted at 69 and is arranged to be pressed upon in the direction of the arrow E by connections actuated from the main control drum. Thus, each time the ring 58, is turned in the direction of the arrow D, the blocks 65 act on the depending arms of the bell cranks 61 as a consequence of which all of the rods 60 are pulled down together.

I claim:

1. A circular knitting machine including, in combination, a series of knitting instruments knitting butts on said instruments, a knitting cam system comprising cams for action on said kniting butts, a further set of butts on the instruments separate and spaced axially from said knitting butts, said separate butts being of two different lengths arranged in a predetermined set-out, a movable cam adapted at required times to act on the separate butts of one length of the purpose of moving corresponding knitting instruments to a non-knitting position whilst knitting instruments corresponding to the separate butts of the other length are disposed in a knitting position, and pickers for action on the butts of the last mentioned length whereby the number of instruments in action for knitting is systematically varied, said pickers being spaced axially from and clear of the aforesaid knitting cam system.

2. A circular knitting machine including, in combination, a series of knitting instruments, knitting butts on said instruments, a knitting cam system comprising cams for action on said knitting butts, the latter being of at least two different lengths interspersed in a pre-arranged set-out capable of being varied according to knitting and patterning requirements, a further set of butts on the knitting instruments separate and spaced axially from the knitting butts, said separate butts being of two different lengths arranged in a predetermined set-out, a movable cam adapted at required times to act on the separate butts of one length for the purpose of moving corresponding knitting instruments to a non-knitting position whilst knitting instruments corresponding to the separatae butts of the other length are disposed in a knitting position, and pickers for action on the butts of the last mentioned length whereby the number of instruments in action for knitting is systematically varied, said pickers being spaced axially from and clear of the aforesaid knitting cam system.

3. A circular seamless hose knitting machine including, in combination, a series of knitting instruments, knitting butts on said instruments, a knitting cam system comprising cams for action on said knitting butts, a semi-- circular series of long, and a complementary series of shorter, additional butts on said knitting instruments, said additional butts being separate and spaced axially from the knitting butts, narrowing and widening pickers which are spaced axially from and clear of the knitting cam system and are adapted for action on the shorter additional butts for the purpose of systematically varying the number of short butted instruments in action for knitting, and, in substantially the same plane as the narrowing pickers, a withdrawable cam adapted whenever it is rendered operative, to act on the long additional butts and move the corresponding instruments to a nonknitting level.

4. A three-feeder circular seamless hose knitting machine including, in combination, a series of knitting instruments, knitting butts on said instruments, a knitting cam system comprising cams at each of the three feeders for action on said knitting butts, complementary semi-circular series of additional butts of respectively different lengths on said instruments, said additional butts being separate and spaced axially from the knitting butts, narrowing and widening pickers which are correspondingly spaced axially from and clear of the knitting cams at two of the feeders for action on the additional butts of one of the semi-circular series, and means for action on the complementary series of additional butts to move the corresponding instruments to a non-knitting position.

5. In a circular seamless hose knitting machine adapted to operate with oscillatory as well as with rotary motion, in combination, a bottom needle cylinder, at superimposed top needle cylinder, a set of double-ended needlesfor operation in said cylinders, sliders in both cylinders for actuating the needles and transferring same from one cylinder to the other according to knitting requirements, each of the sliders in the bottom cylinder being provided with an upper knitting butt, an intermediate transfer butt and a lower additional butt, a cam system surrounding. the bottom cylinder and comprising cams for action on the said knitting and transfer butts, a substantially semicircular series of the additional butts on the bottom sliders being long and the remainder shorter, and narrowing and widening pickers for use in the production of heel and toe pouches during oscillatory motion of the machine, said pickers being spaced axially from and clear of the bottom knitting cam system and adapted for action on the shorter additional slider butts.

6. A circular seamless hose knitting machine according to claim 5, wherein in an extension of the bottom cam box there is provided a movable /z-lift cam adapted, when operative, to act on the long additional bottom slider butts for the purpose of raising the corresponding group of needles (instep needles) to heeling height, the short additional bottom slider butts which are to be acted upon by the pickers being permitted to remain at a low level with the remaining needles (heel and toe needles) at the knitting level.

7. A circular seamless hose knitting machine accord References Cited in the file of this patent UNITED STATES PATENTS 408,180 Kilbourn July 30, 1889 1,198,280 Rush Sept. 12, 1916 2,105,965 Booton Jan. 18, 1938 2,412,248 Bristow Dec. 10, 1946 FOREIGN PATENTS 26,126 Great Britain of 1901 

